SK118699A3 - SHEET METAL STRUCTURAL MEMBER, CONSTRUCTION PANEL AND METHOD OFì (54) CONSTRUCTION - Google Patents

Abstract

A sheet metal structural member for use in the formation of a cast construction panel which member, in turn, comprises a sheet metal web defining a linear edge along one side, and a zig-zag edge along the other side, the zig-zag edge defining wider regions, and narrower regions between the wider regions, and the web extending in a generally triangular fashion from one narrower region through a wider region to the next narrower region, edge formations formed around the zig-zag edge portions of the web and, attachment devices at the apex of each of the wider portions of the web, which may be secured to a construction material. Also disclosed is a construction panel incorporating such structural members, and a method of fabricating such structural members in pairing, and a method of building construction utilizing such structural members.

Description

Method of manufacturing a building panel

Technical field

The invention relates to a method of manufacturing a building panel.

BACKGROUND OF THE INVENTION

Many solutions of prefabricated panels used in building construction are known. Such prefabricated panels make it possible to cover the walls of buildings in a much more economical manner and in a shorter period of time than with conventional methods using bricks, stones, etc.

The use of prefabricated panels allows buildings to be covered with many kinds of different decorative surfaces.

In addition, since the prefabricated panels can be manufactured off site, preferably e.g. In a panel plant, working in such a factory is usually more efficient and at a lower wage cost than on-site work. Furthermore, in the manufacture of such panels, greater accuracy is achieved so that the result is also better.

One of the best known forms of prefabricated panel is a solid concrete panel in which one or more layers of reinforcing steel mesh are cast. These prefabricated panels are usually at least 75 mm thick, but even more.

These panels are extremely heavy and the thermal insulation offered by these prefabricated panels is very small. Changes in outside temperature are quickly transmitted to the interior of the building. As a result, in this form of construction using prefabricated panels, these panels are usually supported by a building structure, which may consist of either concrete columns or steel columns, and the interior walls are usually completed with installed insulation to ensure a constant controllable temperature inside the building.

Due to the high weight of the panels, the anchoring system to which the panels are anchored must be designed with great care in order to withstand all possible stresses caused by both climate and building use, and when built in potentially earthquake areas to be able to withstand to some degree of seismic shocks. All these factors are well known to civil engineers.

Notwithstanding the known disadvantages of such solid prefabricated panels, they have remained in common use for many years despite many attempts to replace them with more economical alternatives.

An example is U.S. Pat. No. 4,602,467, dated July 19, 1986, to H. Schilger, describing the shape of a prefabricated concrete panel that is reinforced with a plain "C" cross-sectional steel. The side sections of the cross-section "C" are formed in different ways and are embedded in concrete. A similar system is also described in Canadian Patent 1,264,957. “C” shaped steel increases the strength of the thin concrete shell that forms the outer wall of the panel.

Using this system, buildings were actually built, with thermal insulation placed between this shaped steel with a "C" cross-section. The surface of the inner wall of the building, mainly in the form of dry wall panels, was directly connected to the inside of the C-profile.

Numerous examples of similar earlier designs are described in the prior art cited in the cited US patent.

However, the use of these types of solutions raises a number of problems. First, concrete and steel have different expansion and contraction coefficients. If these panels are exposed to extreme temperatures, or vice versa, the steel will tend to expand longitudinally or contract more than concrete. As a result, over time, increasing tension or movement between steel and concrete will occur.

Another problem is that the parts of the steel that have been firmly embedded in the concrete create "break lines" that stretch across the panel, usually vertically spaced apart. This is due to the use of a thin concrete shell that reduces the panel thickness to less than 50 mm and in some cases only to about 35 mm. The existence of "break lines" that run through the panels at regular intervals allows breaks to occur when these panels are exposed to unusual impacts.

While these partial disadvantages and risks could not arise to a greater extent, the problem of heat transfer is a much more serious problem. The 'C' metal reinforcement elements, which are firmly embedded in the relatively thin exterior concrete panel of the building, act as ideal transition bridges through which heat passes through the wall in one direction or the other, depending on the season.

This is particularly evident in colder periods, when the ambient air outside the building is cold and the interior of the building is heated, and when the heat passes through the wall with a "C" cross section. These heat losses create cold areas on the inner walls at the reinforcement profiles. These cold regions cause moisture condensation at the above locations, which condenses from the air and settles on the walls. This is known in the construction industry as "shading on the walls" and is unacceptable according to almost all building principles.

When using this system, it is essentially necessary to place an insulating layer around the 'C' profiles, or to install another means of thermal protection in the wall structure so that the inside of the dry wall panels is protected from contact with the 'C' profiles. , which in turn shows that builders are discouraged from using the system by its price.

A very improved design of the building panel that overcomes many of these drawbacks is disclosed in U.S. Pat. No. 4,909,007, issued March 1990, by Ernest R. Bodnar.

This patent describes a prefabricated panel reinforced with sheet metal support elements. The support elements have formed diagonally-transverse supports at a distance from each other that define the openings therebetween. In this way, the heat transfer is reduced, which leads, if not completely removed, to at least a reduction in the "shading" problem.

In this case, it is possible to connect the inner dry wall panels directly to the intermediate elements, which reduces the overall construction costs.

A further advantage of this system is that the side portions of the supports that are designed to be embedded in the concrete are either in the form of folded flaps or punctured openings so that a portion of the concrete can flow through the openings or around the flaps and thus reduce the degree of weakening of the support. Moreover, the problem caused by the different coefficient of expansion and contraction of the two materials is also reduced.

The following patent describing a support also includes a description of a method of manufacturing this support with a relatively high degree of steel loss caused by punching portions of the sheet between the supports. Moreover, although the recessed side portions of the support are provided with openings, their portions are still continuous and this causes to a lesser extent similar problems as described above.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are overcome by the method of manufacturing a building panel according to the invention, which consists in first assembling a plurality of structural elements each consisting of a sheet metal rib having a straight side portion along one side thereof and a zigzag side portion r along the other side. wherein the zigzag side portion defines both the wider regions and the narrower regions, the peaks of the wider region forming the peaks of the reinforced frame structure. Then, the cast building material is poured into a predetermined mold depth, and the reinforced frame structure of the structural members is placed in the cast material such that the ribs partially engage the cast material, after which the cast material cures and the building panel is removed from the formwork.

It is preferred that the rib tops are covered with a synthetic plastic material prior to insertion into the cast material.

According to a further preferred embodiment, the structural elements are arranged parallel to each other, spatially separated, side by side so that the upper and lower frame elements are attached to opposite ends of the structural elements connecting these to a generally rectangular frame structure, the upper and lower frame elements being provided with aperture means. which coincide with the space between the at least one predetermined pair of components.

It is also preferred that the cast building material is poured through the opening means into a space between a predetermined pair of structural members to form a support column.

The total weight of the panel produced by the method according to the invention is substantially lower than that of a conventional prefabricated concrete panel. As a result, it may be a particular means of transport, e.g. a larger number of panels according to the invention are transported by a trailer or a semi-trailer, compared to known panels, thereby significantly reducing the transport costs.

In addition, the lower weight of the panel makes it possible to reduce the foundations of buildings and increase the load on the floor of buildings. Thus, for a given building project, it is possible to build several floors more using the panels according to the invention, while the total weight of the structure remains lower than when using conventional panels.

The handling of the panels according to the invention is much easier. It is no longer necessary for handling equipment such as cranes, etc. to handle such heavy loads as for solid prefabricated concrete. It should be noted that the heat transfer effect of the thermal bridge through the sheet metal construction elements according to the invention is minimized and that, where so-called interior interiors are used. dry interior panels, heat transfer is minimized and "shading" is substantially reduced without the need for extra additional insulation applied to the surface of sheet metal components inside the building, as was necessary in the past.

Spaces between any two steel studs t _t panel can be used for pouring vertical columns supporting the building construction.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic perspective view showing a building in the first stage of its construction

Fig. 2 is a schematic view of the same building showing the next stage of its construction.

Fig. 3 is a perspective view of a typical partial-section building panel showing its structure.

Fig. 4 is a part of FIG. 3. on a larger scale.

Fig. 5 is a sectional view taken along line 5-5 of FIG. 4th

Fig. 6 is a cross-sectional view taken along line 6-6 of FIG. 4th

Fig. 7 is an enlarged cross-sectional view in the direction Ί-Ί of FIG. 6th

Fig. 8 is an enlarged perspective view of a portion of a structural member.

Fig. 9 is a cross-sectional view of a further embodiment of the component corresponding to FIG. 6th

Fig. 10 is a cross-sectional view showing a further embodiment of a component corresponding to FIG. 9

Fig. 11 is a cross-sectional view showing another embodiment of a structural member.

Fig. 12 is a section corresponding to FIG. 6th

Fig. 13a is a plan view showing a sheet metal blank, in a first stage of forming one pair of structural members according to the invention.

Fig. 13b is a plan view corresponding to FIG. 13a at a later stage of forming of this pair of components.

Fig. 13c is a schematic cross-section showing an even later stage of forming the pair of components of FIG. 13a and 13b.

Fig. 14 is an elevational view of another embodiment of the invention.

Fig. 15 is a perspective view showing an example of joining together two parts of a structural member.

DETAILED DESCRIPTION OF THE INVENTION

Building panels are manufactured in a panel building outside the construction site. In the manufacture of a building panel, a plurality of structural members 30 are first assembled, each consisting of a sheet metal rib 44 having a straight side portion 40 along one side thereof and a zigzag side portion 42 along the other side, where the zigzag side portion 40 defines both wider areas 60 and narrower regions 62. The peaks of the wider region 60 form the peaks of the reinforced frame structure. The substantially horizontal mold (not shown) is laid on a flat surface. The concrete is poured to a predetermined depth in a prepared mold, which can additionally be provided with an external surface treatment. A rectangular reinforced frame structure of structural members 30 and plate members, as shown in FIG. 3, is pre-assembled in the workshop. The network of reinforcing wires 28 may simply be tied or attached to the ribs by wire clips X (FIG. 5). This reinforcing frame structure is placed in the cast concrete so that the ribs partially extend into the concrete to a depth corresponding usually to half the thickness of the panel being cast. After the concrete has hardened, the building panel is removed from the mold.

In some cases it may be desirable to insulate and pre-finish the walls already in the panel shop. This is readily accomplished by placing an insulating material (not shown) between the sheet metal structural members and connecting internal wall panels such as e.g. called. dry wall panels p. (Fig. 5), to the straight edges of the ribs.

Also, if the panels include window openings, the windows into these openings may be installed in the panel building before the panels are sent to the site.

The total weight of the sheet metal panel according to the invention is substantially lower than that of a conventional prefabricated concrete panel.

In FIG. 1 and 2, a relatively simple building is shown in which building panels 22 made according to the method of the invention have been used. Fig. 1 shows the first floor of a building 10 with completed walls 12, 14, 16, 18 and a concrete poured floor 20. In FIG. 2 shows the unfinished second floor of the building of FIG. First

FIG. 2, the walls of the building are constructed of prefabricated cast building panels 22. Some of these panels provide a clean wall surface, others include window openings 24a, and others include door openings 24b.

Some of the panels for certain buildings may also have a modified exterior surface (not shown), which may consist of a variety of materials, ranging from glass to marble, brick imitation, metal, gravel surface to synthetic plastic.

Methods for making such panel surface treatments are well known to those skilled in the art, so no further description of these modifications is necessary.

In FIG. 3, a typical cast building panel 22 is shown. This panel 22 comprises an integral layer 26 of castable material, in this case concrete, reinforced with a network of reinforcing wires 28, as is well known in the art. For example, the cast material may have a thickness of from 25 mm to 37.5 mm or 50 mm, which in any case will be much thinner than would correspond to a layer of unreinforced concrete material as known in the art.

The layer 26 is further reinforced by a plurality of metal sheet elements 30 separated from each other. In practice, the metal sheet elements 30 are spaced apart e.g. 600 mm, although in some cases a distance of 400 mm is required. Nothing, of course, excludes any other distances of the sheet metal members 30, provided that these distances only have to meet the building construction requirements.

These vertical sheet metal members are provided with horizontal top and bottom plate members 32 and 34 which provide the entire frame structure for the panels. The plate members 32 and 34 may be made of the same material as the sheet metal structural members 30 or other desired material in different shapes and cross-sections.

In the case of FIG. 3, the plate members 32 and 34 are shown in the form of a single U-shaped profile having walls 32a. 34a and side walls 32b. 34b.

As will be apparent from the following description, both the structural members 30 and the plate members 32 and 34 are made of sheet metal, preferably formed by cold rolling technology, which provides high production productivity and desired quality.

In FIG. 4, 5, and 6, the structure of the sheet metal member 20 is shown in more detail.

The sheet metal member 30 comprises a first substantially straight side portion 40 and a second substantially cranked side portion 42. Between the side portions 40 and 42 extends from one of them to the other a variable width sheet metal 44 and as shown substantially zigzag shape.

The linear side portion 40 of the sheet metal member 30 can be made with different cross sections to achieve different properties. In the example shown in FIG. 4, 5 and 6, the straight side rib portion 40 is formed into a triangular stiffening tubular portion with band portions 46, 48, 50, and one means 52 for closing the tubular portion. Said means 52 are formed by an edge strip which extends parallel to the rib and is secured thereto by, for example, spot welding or other suitable means. In the example described, the connection is made by riveting 53 (FIGS. 6 and 7), in which a punch is pressed into the sheet and the sheet is extruded into an enlarged cutout in the punch so as to form a connection of two pieces of sheet (FIG. 7). This type of connection represents only one of the various suitable rib-to-belt connections.

It has been found that this hollow triangular reinforcing tubular member has great strength and structural rigidity.

Such a shaped sheet metal component has a high load-bearing capacity and can be used for the external walls of buildings.

With the appropriate choice of the dimensions and thickness of the sheet, similarly shaped sheet metal structural members can be used as floor beams for supporting the floor, and also roof or ceiling structural members can be manufactured in such a manner.

At the required lower load-bearing capacity and for the inner walls, it is not necessary to form a triangular reinforcing tubular part along the straight side portion.

The metal rib 44 has generally triangular shapes having apexes at the wider regions 60 and tapering at the narrower regions 62. A continuous edge strip 64 is formed along the free edge of the rib, and its zigzag shape extends from apex to taper, back to apex, etc. wider areas of the rib, ie however, at least at the vertex locations between any two rib constrictions, the apertures 66 are preferably, but not necessarily, punctured or formed. Preferably, a rim 68 is formed around the edge of the aperture 66.

Thus, the effect of the thermal bridge of the rib is limited because the rib at the apertures does not contain metal.

FIG. 5, 6, and 8, each of the rib tops has a bent tongue 70 and a free bore 72 which form anchoring means for the cast panel. Preferably, each tongue 70 is bent to one side of the rib, opposite to the side where the rib is widened by the edge strip 64.

The tongues 70 and strips 64 on opposite sides of the rib thus form the panel connecting means while achieving the advantages described below.

In order to reinforce the thin concrete panel as shown in FIG. 5, on one side of the panel, the apexes of the sheet metal members are poured into the concrete to a depth sufficient to cover the apertures 66 formed at the apexes of the ribs, for example to a depth of about 19 mm in the case of a 125 mm panel.

Thus, each of the rib tops is securely embedded in the material, and the material can flow around the fasteners comprising the rib strip 64 on the one hand and the tongue 70 arched out of the rib on the other, and through the holes 72 thereby creating a well secured connection of each sheet metal construction. element along its apex.

Between these peaks, the sheet metal structural members have no connection to the cast panel. As a result, the differences in the extensibility and contraction rates between the sheet and the cast material are small and without affecting the safety of the connection of the cast material and the sheet metal members.

Of course, it is contemplated that the panels may be easily attached to a building skeleton that may be constructed of concrete pillars or structural steel pillars to form exterior walls on the skeleton. Furthermore, if desired, the panels can also be used to form interior walls.

The panels can be manufactured with various surface finishes, surface effects and details as known in the art.

It can also be seen that the 600 mm spacers form part of the approximately rectangular load-bearing structure, providing a great way to secure the position of the panels on the building, while allowing minimal heat transfer from the interior to the exterior of the building. In addition, the expansion and contraction of the steel due to the thermal effect in relation to the concrete panels has a negligible effect on the safety of joining the top portions of the sheet metal members to the panels.

The spaces between any two sheet metal structural members in the panel may, if desired, be used to cast vertical columns of the building's structural structure. These columns are shown in FIG. 1 and 2 marked C.

The shuttering panels 73 for forming these columns C (FIG. 3) can be attached to any adjacent pair of sheet metal members 30,

The apertures 73a and 73b formed in the upper and lower portions respectively, respectively. The lower plate members 32, 34 correspond to their space locations between the selected pair of sheet metal members 30. The reinforcing steel wires are connected between the two sheet metal members 30 in a conventional manner.

When the panel is so assembled and placed on the structure of the building being built (Fig. 2), the columns may be cast in place, e.g. using a normal concrete pouring vessel.

When the next floor of the panels is erected, similar formwork 73 and openings 73a, 73b will be positioned opposite the columns in the lower panel so that the load-bearing columns of the building will be continuously cast in the section from one floor to the next floor at the same time the floor 20 is also cast at the same time.

As a result, the entire building is cast on individual floors and each floor and its columns form a continuous homogeneous structure of the building.

The formwork 73 can be removed after the building material has cured. In some cases, this formwork can form part of the finished interior wall of the building and is therefore left in place.

It will also be apparent to those skilled in the art that, if necessary, the C-pillars could be cast into the wall panels in the prefabricated building outside the construction site. In other words, both wall panels and columns can be prefabricated in off-site operations.

As described below, the panels 22 may be placed in place, fastened the bottom of each prefabricated column to the floor 20, and after erecting the ceiling beams and formwork for the next floor floor casting, then cast the next floor 20,

The peaks of the wider regions 60 of the ribs 44 may be coated or immersed in a suitable synthetic plastic material, for example a resin-based material may be used and the coating or coating may be applied as shown in FIG. 8, layer 74. The effect of using a cover layer at this point is doubled.

In particular, the cover layer constitutes an additional heat barrier for the transfer of heat between the panel concrete and the sheet metal members. In addition, another protective layer of sheet metal components, which are mostly made of galvanized sheet metal, to be corrosion-resistant, is however not always a permanent solution to the corrosion problem. It is therefore preferred that the sheet of structural members is substantially completely insulated from the concrete by a coating layer 74 formed at their apexes. Corrosion as a result of moisture or other chemicals contained in concrete or other cast material is thus eliminated.

It is clear from the above description that sheet metal construction elements for panels, joists and other elements can be made in different shapes and for different requirements and purposes.

Fig. 9 shows a second sheet metal member 80 provided with openings 86 passing therethrough.

The peaks 88 of the second sheet metal member 80 are formed essentially as in the case of the sheet metal member of FIG. 5th

The straight edge 82 of the sheet metal member has a single " C " cross-section including a front waist portion 90 and a reinforcement waist 92.

Although the second sheet metal members will not have as much load carrying capacity as the sheet metal members shown in FIG. 5, can be used in many cases for paneling the outer walls where the paneling does not have to carry significant loads. Furthermore, they can be used for interior walls and partitions of buildings.

In FIG. 10, another shape of the sheet metal member is shown. In this case, the third sheet metal member 100 is provided with a rib portion 102 with a zigzag edge 103 and apertures 104 formed therein. The straight edge 106 has, as in the example of FIG. 5, the shape of a triangular tubular formation. The apexes 108 are formed in the rebre.

In order to form a different kind of connection, a "U" profile 110 is attached along the ribs of the rib, which is attached thereto e.g. In order to provide thermal protection, a layer of synthetic plastic material 114 is interposed between the peaks and the "U" profile 110.

Fig. 11 shows yet another possible shape of the sheet metal component. In this case, the fourth sheet metal member 120 has a rib 122 with apexes 130. a zigzag edge 123 and has apertures 124 and a straight edge 128. The straight edge 128 is formed as a cross-section "C" similar to FIG. 9. A " U " profile 132 is attached to the rib peaks 130. The thermal protection is formed by plastic means 132. The " U "

Obviously, using the various cross-sections shown, it is possible to construct and produce sheet metal structural members for assembling lightweight wall panels. It is also possible to produce load-bearing joists and other heavy-duty structural elements, for floors, roofs and similar parts of buildings after increasing the demands on sheet metal construction elements.

For example, the structural members of the invention, as shown in FIG. 12, used as a joist 150 for supporting the floor. The floor is cast from a concrete material and for this purpose horizontal formwork, which is known in the art, is necessary. The joists 150 are made in a similar embodiment to that shown in FIG. 5, 6 and 8. The precise sheet thickness and the dimensions of the ribs are suitably adapted so that the ribs have adequate load-bearing capacity for a given span of the structure being built.

FIG. 12, it will be appreciated that the joist 150 having the tops 152 may be embedded in a floor which is cast directly in the building so that the floor is formed in one piece without joints and is supported by joists placed in a very advantageous and economical manner.

For this purpose, the joists are laid across the building at appropriate intervals, e.g. 600 mm, or the spacing can be selected as required in specific buildings. The formwork panels 153 are then located between the joists and slightly lower than the joists 152 and their respective tongues 154.

A formwork clamp system 160 is provided to support the formwork at this level. The clamps 160 consist essentially of a lower rod member 162 and a pair of upper rod members 164. Links 166 connect the upper rod members to the lower rod member. The links 166 also connect the rod members 164 to the control screw 168 and the nut 169. By means of the handwheel 170 or other suitable element it is possible to rotate the screw and thus push the scissor lever mechanism outwards and upwards. This causes the members 166 to move upwardly and thereby move the upper bar members 164 relative to the lower bar member 162. In this way, the shuttering panels can be held at the desired level, with the joist tops 152 extending above the shuttering panel 153,

When the concrete is then cast onto the shuttering panels, it can flow around the tops of the joists, essentially as described in connection with the panels in FIG. 3 and 4.

The floor is then allowed to cure, resulting in an integral monolithic structure. Then the formwork is simply removed by loosening the screws and removing the clamps and formwork from the bottom of the floor.

This is shown schematically in FIG. 2, where part of the floor 20 is already cast and the part of the formwork with the tops 152 of the joists 150 protrudes up from the formwork.

Of course, the scale and the relative sizes of the various components are shown in FIG. 2 slightly changed.

Two of these structural members of the invention may be joined together to form a single composite structural member having greater strength and load bearing capacity. Such a composite member 180 is shown in FIG. 14th

The composite member 180 includes a lower member 182 and an upper member 184. Both of these members 182, 184 are identical and substantially similar to the member shown e.g. FIG. 5th

The two components 182. 184 are positioned such that the peaks 186 of their ribs are in contact with each other. The peaks 186 are connected or secured to each other in any suitable manner, for example by spot welding or the like.

Preferably, the peaks 184 are provided with flat regions 188 to provide a secure, firm connection, thereby achieving a high degree of integrity and bond strength between the two structural members.

This composite member will then have unique properties in that it can be made cheaply from sheet metal and has a high strength and load bearing capacity in relation to the weight of the metal for a certain length of the member. In addition, the manufacturing cost of this composite component is considerably lower than the cost of constructing components having a corresponding length using conventional methods.

According to another highly preferred embodiment of the invention, the components are preferably formed by cold rolling and cold forming methods as shown in FIG. 13a, 13b and 13c. Basically, it is possible to form two separate structural elements from one continuous sheet metal strip. This reduces unnecessary sheet metal losses that were inherent in earlier punching of the structural members as described in the aforementioned U.S. Patent 4,909,007. As shown in FIG. 13a, the sheet web 200 of a suitable size, preferably galvanized, passes through a forming line, during which the web 200 is divided along the zigzag dividing line 202 into two web portions 200A and 200B to form ribs with apertures, as shown e.g. FIG. It is preferred that the apertures 204 are formed in the ribs during this continuous cold forming process.

In the next section of the cold forming process, the flange band formations 206 are formed along the zigzag edges of both band portions 200A and 200B. (Fig. 13a). In this way, flange band formations are formed on the finite, previously described components.

It can be seen that the dividing trajectory 202 is closest to the belt edge at the apex 208 of each rib and furthest from the belt edge at the neck 210 of each rib.

As a result, the skirt strips 206 that are formed along the zigzag edge of each of the two belt portions 200A. 200B varies their width from the minimum at the top 208 to the maximum at the throat 210. This provides the structural member, where necessary, valuable additional strength.

Similar second skirt strips 212 are formed around the apertures 204 and are folded outwardly in the same forming operation.

Further apertures 214 are formed at the apexes 208 of each rib, and the material punched out of these apertures 214 forms the tongues of the structural elements that are shown e.g. FIG. 5th

The flange band folds 216 formed on both sides of the web 200 form the first flange band formations. The second flange band folds 218 are formed spaced from the folds 216 parallel to them (see FIG. 13c). The belt is bounded by its two free edges 220.

Thus, along the edges of the two supports, a straight side cross-sectional "C" cross-section is formed as in the embodiment shown in FIG. 9. The pair of supports thus formed is shown in front view in FIG. 13c.

The formation of these edges is carried out by a continuous rolling mill, which is placed in a forming line downstream of the dividing portion of the line so that the zigzag cutting and hemming of the zigzag edge and apertures is placed first and subsequently the straight side stripes are formed by successive bending.

Continuous zigzag splitting and stamping can be accomplished, for example, by the apparatus described in U.S. Patent 4,732,028 of March 22, 1988 to Ernest R. Bodnar. This device is especially suitable for cold forming of sheet, its cutting and forming of hem formations in a continuous continuous operation.

This device is not described in detail here, because it is described in sufficient detail in the above-mentioned patent.

Fig. 15 shows an alternative method of securing the free edges of the straight strips in the intermediate portion of the rib. In this case, the tongues 230, 232 are molded in both free edges of the rib, respectively. in its intermediate part. The tongues are folded, as shown, to join the two ribs together.

The foregoing description of preferred embodiments of the invention is given by way of example only. The invention is not limited to any particular features described herein, but includes all variants thereof that fall within the scope of the appended claims.

Claims (4)

A method for manufacturing a building panel, characterized in that a plurality of structural members are first assembled, each consisting of a sheet metal web having a straight side portion along one side thereof and a zigzag side portion along the other, wherein the zigzag side portion defines both wider the region and, on the other hand, the narrower regions and the sheet-metal rib are shaped like a zigzag from the narrower region through the wider region to the next narrower region and form peaks on the wider regions and form the same in the reinforced frame structure; and the reinforced frame structure of the structural members is placed in the cast material such that the ribs partially engage the cast material, after which the cast material cures and the building panel is removed from the mold. Method according to claim 1, characterized in that the rib tops are covered with a synthetic plastic material before being inserted into the cast material. Method according to claim 1 or 2, characterized in that the structural elements are placed parallel to each other, spatially separated, side by side, such that the upper and lower frame elements are attached to opposite ends of the structural elements connecting these to a generally rectangular frame structure, wherein the upper and lower frame members are provided with aperture means which coincide with the space between the at least one predetermined pair of components. Method according to claim 3, characterized in that the cast building material is poured through the opening means into the space between a predetermined pair of structural members to form a support column.